Seven areas within the surrounding communities are scheduled for quarterly noise measurements.  These locations were chosen from the Pease International Tradeport Federal Aviation Part 150 Study.  It is our goal to build a database of noise measurements so that changes in the noise impact can be studied on a consistent basis. 

The areas to be measured include Sherburne Village and The Woodlands in Portsmouth, Foxpoint Road in Newington, Deer Meadow Road in Durham, Farmwood Village in Dover, Locke Road in Rye and Greenland Town Hall.  A sound level meter is also located at the midpoint of the runway during the measurements.  The corresponding measurement is also given. 

Requests for noise monitoring can be made by contacting the Community Liaison, Amber Goodspeed, at (603) 433-6536 or leave a message at the noise line (603) 436-6333.  Requests will be made on a space available basis.

Noise monitoring has been temporarily suspended.  Please check back at a later date.

PRINCIPAL DESCRIPTORS OF ENVIRONMENTAL SOUND 

There are several descriptors used in the assessment of aircraft noise.  The following are the most commonly used and describe different aspects of sound.  The definitions are presented with the purpose of allowing the reader to attain a general understanding of the metrics rather than the technical specifics that are associated with such terms. 

dB(A) – Decibel (logarithmic unit of acoustical measurement) on an a-weighted scale. An (A) weighting in noise monitoring increases the values of sounds within the frequencies that the human ear hears most readily and decreases those that aren’t.  A-weighting is specified in the Federal Aviation Regulation Part 150 as the weighting to be utilized when measuring aircraft noise. 

Lmax and Lmin – The highest and lowest instantaneous sound levels within a certain time period.  For the table presented, each is shown for every hour and each is shown for the entire measurement period in the summary. 

SEL – Sound Exposure Level – This metric is the unit used to describe the total amount of sound for an event.  All of the sound is totaled and compacted down into a one second reading.  An SEL for an aircraft fly over would be the noise level experienced if it took one second for the entire sound of the aircraft flyover to occur. 

Leq – Equivalent sound level – average sound level of a time period.  (This is as simple as an average of five numbers except it is on a logarithmic scale instead of a linear scale.) 

Ln – Ln percentiles – these are statistical numbers for a series of readings.  For example, L90=43 means 43 dBA was exceeded 90 percent of the time.  These results are found in the summary information.